Positive predictive values for detection of trisomies 21, 18 and 13 and termination of pregnancy rates after referral for advanced maternal age, first trimester combined test or ultrasound abnormalities in a national screening programme (2007–2009)
2014
OBJECTIVE: The objective of this article is to analyse the positive predictive value (PPV) of trisomies 21, 18 and 13 after referral for advanced maternal age (AMA), first trimester combined test or ultrasound findings to suggest improvements for clinical practice. METHODS: Data (48 457 combined tests, 134 000 fetal anomaly scans and 24 379 invasive prenatal tests) were combined to calculate PPV and termination of pregnancy rates. RESULTS: For referral for AMA, the PPV for T21 was 1.0% and 1.8% for amniocentesis and chorionic villus biopsy, respectively; for the combined test at a maternal age >/=36 years, these percentages were 4.9% and 12.5%, respectively and for maternal age 90% unless detected after referral for ultrasound findings (71.5-85.9%). About 50% of pregnant women with a high combined test risk chose not to have invasive testing. CONCLUSIONS: Advanced MA is still a large contributor to invasive testing but should be abandoned (low PPV, high fetal loss rate) and be replaced by reimbursable combined test screening for all women. Patient information on second trimester ultrasound screening should indicate that abnormal ultrasound findings are associated with high trisomy rate. (c) 2013 John Wiley & Sons, Ltd.
Keywords:
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
9
References
14
Citations
NaN
KQI